Terminal A is home to one of BOS'top airlines, Delta. It is also the home to Continental (for now), and NW ops are coming here as the merger with Northwest comes together. Interestingly, DL didn't even serve BOS until its 1972 merger with Boston hometown carrier Northeastern. JetBlue, USAir, American, and Delta are all very close in market share as this airport has no dominant hub carrier. Logan's newly built Terminal A, which replaced a previous building that was once occupied by Eastern Airlines, opened to passengers on March 16, 2005. The building is the first airport terminal in the United States to be LEED certified for environmentally friendly design by the U.S. Green Building Council. Among the building's features are heat-reflecting roof and windows, low-flow faucets and waterless urinals, self-dimming lights, and storm water filtration. The 22 gates in Terminal A increase the number of gates at Logan to 102.